In 1995, the Federal Aviation Administration (FAA) initiated its “Free Flight” air traffic modernization program in order to improve airspace efficiency and capacity, and also revolutionize air traffic control. Essentially, the Free Flight program is designed to provide users (e.g., pilots, flight crews, aircraft operators, airlines, etc.) with as much flight mission flexibility as possible, while also enhancing the safety and predictability of the National Airspace System. Advantageously, the Free Flight program is expected to give aircraft operators increased control over their flight missions, and the opportunity to better control their operating expenses as a result. In other words, aircraft operators will benefit financially by having increased autonomy and control over the planning and execution of their flight missions.
Currently, it is the responsibility of FAA air route traffic controllers to determine the specific routes and waypoints used by aircraft to reach their destinations. A waypoint is a fixed location with a specified longitude and latitude. Typically, in order to traverse a route, a pilot navigates to the nearest waypoint, and then to the next waypoint in turn, and so on until the aircraft reaches its destination. Currently, the FAA does not require an aircraft to reach a waypoint at a specific point in time. However, in the future, under the Free Flight program, the FAA will give operators more control over the route selections, but their aircraft will be required to reach specific points at specific times. In other words, under the Free Flight program, an aircraft will be required to arrive reliably at a predetermined location (e.g., waypoint) at a predetermined time, also known as a Required Time of Arrival (RTA).
Notwithstanding the numerous advantages of the Free Flight program, a significant problem has arisen with respect to the capabilities of existing navigation systems that limit the ability of aircraft to reliably meet the air route (waypoint) time constraints imposed. For example, there are numerous onboard aircraft, ship-borne and motor vehicle navigation systems that can calculate and display an Estimated Time of Arrival (ETA). However, there is no navigation system currently available that displays an indication to an operator that allows the operator to easily determine whether or not a required waypoint time constraint can be reliably satisfied. Also, there is no navigation system currently available that provides an interactive indication to an operator of a vehicle's (e.g., aircraft, ship, motor vehicle, etc.) progress in meeting any routing (waypoint) time constraints imposed. Therefore, it would be advantageous to have a system and method that can compute a vehicle's motion in four dimensions (e.g., three spatial dimensions and time) and reliably predict the vehicle's arrival time at a predetermined waypoint, by providing a graphical display to an operator of the vehicle's progress that enables the operator to adjust the vehicle's movement and achieve the desired arrival time. As described in detail below, the present invention provides such a system and method, which resolves the existing navigation and control system problems in reliably meeting routing time constraints imposed and similar other problems.